Sometimes, you need a healthy make-ahead breakfast. Whether you’re serving a crowd or trying to ease busy weekday mornings, this breakfast casserole is just the ticket.
Typically, breakfast casseroles includes sausage and potatoes. I loaded this one up with fresh veggies and greens instead, including red bell pepper, green onion and spinach.
Creamy feta or goat cheese rounds it all out. You don’t need a ton of dairy to achieve a lovely, luxurious texture. This is a lightened-up dish that seems more indulgent than it really is.
This healthy breakfast casserole is the perfect addition to a holiday breakfast spread. Since it offers some protein and vegetables, it’s a great way to help balance those delicious carb-heavy treats, like muffins and pancakes. I’d be thrilled to find this option alongside bagels and cream cheese. Leftovers are good for lunch, too.
To develop this recipe, I followed my foolproof frittata formula. It’s easy to make, colorful and delicious!
How to Make Breakfast Casserole
You’ll find the full recipe below, but here’s a brief summary:
- Sauté the bell peppers and green onion until tender, then add spinach and cook until wilted. Set the pan aside for a few minutes to cool, so the warm veggies don’t cook the eggs when we stir them together.
- Whisk together the eggs with a dash of full-fat dairy, like whole milk or Greek yogurt, plus some salt and pepper. Stir in half of the cheese (we’re reserving the other half for topping the casserole).
- Transfer the veggies into the egg mixture, stir to combine, then gently pour it all into a buttered baking dish. Top with the rest of the cheese.
- Bake until the eggs are cooked through. That’s it!
How to Prepare This Casserole in Advance
Prepare the mixture as instructed, but refrigerate the egg and veggie mixture in a mixing bowl or in the buttered baking dish for up to two days.
Bake as directed, knowing that your dish may require a few extra minutes in the oven since it’s starting off cold (especially if you refrigerated in the baking dish).
Watch How to Make Healthy Breakfast Casserole
Breakfast Casserole Serving Suggestions
This breakfast casserole would fit in nicely with any breakfast spread. Here are some general suggestions:
- Avocado Toast or any other toast
- Bagels with cream cheese and toppings
- Crispy Hash Browns, which you can make in a skillet while the frittata cooks
- Muffins, pancakes and waffles
- Salads, for an all-around healthy meal
Please let me know how your breakfast casserole turns out in the comments! I love hearing from you.
Healthy Breakfast Casserole
- Author: Cookie and Kate
- Prep Time: 10 minutes
- Cook Time: 40 minutes
- Total Time: 50 minutes
- Yield: 8 servings 1x
- Category: Breakfast
- Method: Baked
- Cuisine: American
- Diet: Vegetarian
Make this healthy breakfast casserole recipe for the holidays or busy weekday mornings! Featuring red bell peppers, spinach and creamy cheese, this casserole is wholesome, hearty and full of fresh flavor. Recipe yields 8 generous servings.
Ingredients
- 1 tablespoon extra-virgin olive oil
- 2 medium red bell peppers, chopped (about 2 cups)
- ¾ cup thinly sliced green onion (about 1 small bunch)
- 5 ounces roughly chopped spinach (about 5 cups)
- 12 eggs
- 3 tablespoons full-fat dairy (heavy cream, half-and-half, whole milk, sour cream or yogurt)
- Several dashes of your favorite hot sauce, like Cholula
- ½ teaspoon fine salt
- 10 twists of freshly ground black pepper
- 4 ounces (1 cup) crumbled feta or goat cheese
Instructions
- Preheat the oven to 350 degrees Fahrenheit. Grease a 9 by 13-inch pan with butter (don’t be tempted to use cooking spray; it doesn’t work nearly as well).
- In a large skillet, warm the olive oil over medium heat until shimmering. Add the bell pepper and green onion and cook until the pepper is tender and cooked through, about 8 to 10 minutes.
- Add the spinach to the skillet and cook, while stirring, until wilted, about 2 minutes. Set the pan aside to cool for a bit while we prepare the egg mixture.
- Crack the eggs into a medium mixing bowl. Add your dairy of choice, several dashes of hot sauce, plus the salt and pepper. Whisk just until the egg yolks and whites are blended.
- Stir in half of the cheese (we’re reserving the other half for topping the frittata before baking). Transfer the lightly cooled veggies into the bowl, and stir to combine.
- Pour the mixture into the prepared pan. Evenly disperse the remaining cheese on top.
- Bake for 25 to 35 minutes (keep an eye on it), until the eggs are puffed and appear cooked, and the center of the frittata just barely jiggles when you give it a gentle shimmy. For good measure, insert a fork about ¼-inch into the center of the eggs and make sure the fork comes out clean
- Place the frittata on a cooling rack until you’re ready to serve. Slice with a sharp knife, and serve. Leftovers will keep well for about four days in the refrigerator. Enjoy leftovers chilled, at room temperature, or gently reheat in the microwave or oven.
Notes
Prepare in advance: Cover and refrigerate the mixture until you’re ready to bake (it should keep well for up to two days). Bake as directed, but know that your dish may require a few extra minutes in the oven since it’s starting off cold.
Change it up: I love the flavors you see here, but you can definitely use other vegetables in similar quantities. More hardy greens like kale or chard will require a bit more cooking time. Find other flavor variations on my frittata post.
Can I freeze it? I don’t recommend freezing leftover breakfast casserole. When I defrosted my frozen slices, they turned very watery and slightly rubbery. If you’re looking for a good egg-based freezer recipe, check out my breakfast burritos.
Vegetable enthusiast. Dog lover. I'm probably making a big mess in my Kansas City kitchen right now. 
MMillsap
ANy idea what the nutritional data is? I am doing food prep and that would be HUGELY helpful.
Kate
Hi, the nutritional information is below the notes section of the blog.
Sophie Rochefort
Nous avons adoré cette recette, et toute la famille se réjouit à l’idée d’y regoûter rapidement! Merci tellement!
Sanndy
I’ve made your recipe and it’s delicious! I was wondering next time if I could mix asiago cheese along with the feta? Thank you!!
Kate
You can try it! Let me know what you think, Sanndy.
Toni Gennarelli
It does not tell me to increase the size of the pan if you are doubling the recipe. Should I use a bigger pan? Also is it ok to use an aluminum pan?
Kate
You could split it between two pans. Or, you may need to increase the cooking time if you use the same 9×13.
Toni Gennarelli
Actually, I got the right size pan. Everyone liked it! Thank you!
Mimi
Made this dish this morning and we loved it. Hubby was surprised he liked a breakfast casserole without hash browns and sausage. So healthy and so delicious. I’m in reduced salt diet; hubby is on low sugar, low carb diet due to our health issues. Thank you for including the nutrition information. I used frozen precut spinach which made it much easier. This has made our regular rotation dish list!
Kate
I love to hear that! Thank you for sharing, Mimi.
Karen
I just finished assembling the breakfast casserole-my fourth iteration-and will bake it in the morning. This time I was out of spinach so grabbed some Swiss chard from the garden. I have added mushrooms, chopped tomatoes, parsley, even cilantro in the past. All have been delicious. I serve with a faux aioli that I make with mayo and pesto. The best. Next time I will experiment with “egg muffins” using my muffin tin. Has anyone tried that?
Jen
I am not sure if it’ll let me reply to you since I’m not the author, but we did the muffin tins. We call them egg bites or egg We did two batches one using a 12 muffin tin and one using a 6 muffin tin which of course made them larger. Much prefer the larger egg muffin or the original size. The smaller ones were dry and we didn’t overlook them. Good luck!
Karen
Thanks Jen…I will try the larger muffins.
Sandie
Love this recipe! So versatile- I added mushrooms, white onion, fresh garlic and chopped chicken/sage sausage. Also switched up the spices added smoked paprika and Italian seasoning. Sounds random but both together are delicious.
Makes for a great healthy and premade breakfast or the week for both me and the hubs!
Kate
Great to hear, Sandie! Thank you for your review.
KATHLEEN D BROCK
So i could use broccoli instead of Spinach?
Kate
Sure, you will just want to make sure you cook it some first.
Laura P
Brought this to women’s prayer meeting this morning. Everyone loved it and wanted the recipe. It fit perfectly with my keto eating plan. I added a box of 10 Jones fully cooked turkey link sausages (cut lengthwise then chopped). I threw in a few more eggs and doubled the Feta cheese (4 ounces in the mixture and 2 ounces on top after it came hot out of oven). Will definitely make it again… delicious looking and delicious tasting. Thank you!
Kate
You’re welcome, Laura!
Hannah
SO good!! I added 1lb of breakfast sausage + 3 eggs and it turned out perfect!
Deda1223
I made this today for a Mother’s Day lunch. The only change was the addition of cubed ham (about a cup). It was a HUGE hit! My Mom made sure I saved the recipe. Thank you, Kate!
Kate
You’re welcome, Deda!
Mindi Hartman
I made this casserole for friends who were coming to lunch today. It was easy to make and turned out perfectly. Everyone enjoyed it. I used goat cheese this time. We were four people and I would say I probably have one to two portions at the most left over. I served it with a salad. Great recipe Kate!
Kate
I’m happy to hear you enjoyed it, Mindi! I appreciate your review.
Gracie
I just made this and it is so tasty! This is going to become a staple in my meal prep recipes for sure :)